Eliam_Dar said:
that cannot happen, you are assuming that the force is transfered, which in that case will make the unmovable object to start moving, thus changing that condition.
Not if the universe suddenly becomes mirrored in a span of time shorter than the Planck Time.
Either way here's another theory: The unstoppable one (object or force, although one doesn't exist without the other so that point is moot) moves onto the unmovable one and absorbs it, becoming part of the unstoppable because the only possible unstoppable force is a black hole, so the unmovable never has to move because it remains fixed once it enters the black hole and the black hole is able to go on it's merry way.